Physiological Responses of the Tetrastigma hemsleyanum Plant under Different Color Films

Abstract

Tetrastigma hemsleyanum is a traditional Chinese medicine herb, commonly used for its anti-inflammatory and antitumor properties. Flavonoids are the main functional constituents of T. hemsleyanum, and their production in the herb is affected by light quality. T. hemsleyanum is a shade-loving plant and is usually covered by black shade nets during cultivation. However, there are only a few studies on the effects of using color films on growth and flavonoid synthesis in T. hemsleyanum. In this study, we measured the influence of five different color films on growth indexes—sugar, soluble amino acid, soluble protein, and flavonoid content—and flavonoid-synthesizing enzyme activities in T. hemsleyanum. The films used were colorless plastic film as the control group (CK-W), red film (RF), yellow film (YF), green film (GF), and blue film (BF). BF promoted plant growth and increased yield, as evidenced by the highest growth indexes, soluble amino acid content, and chalcone isomerase (CHI) enzyme activity. RF increased the content of secondary metabolites, thereby enhancing herb quality, as evidenced by the highest phenylalanine ammonia lyase (PAL) activity and increased flavonoid content.

Flavonoids metabolism and physiological response to ultraviolet treatments in Tetrastigma hemsleyanum Diels et Gilg

“…The determination of flavonoid monomers was performed as described by Bai et al (2021) . Approximately 0.1 g freeze-dried L or R were ground into fine powder (80-mesh sieve) and placed in a 2 ml Eppendorf tube.…”

“…Total flavonoid contents in L and R of T. hemsleyanum were determined by a UV–visible (UV-VIS) spectrophotometer (UNICO 3802, Shanghai, China) in accordance with the method of Bai et al (2021) . Supplementary Method 1 provides more details on the experiment.…”

“…Phenylalanine ammonia-lyase (PAL) enzyme activity was determined following the method of Bai et al (2021). We obtained 1 ml crude enzyme solution, 1 ml 0.33% phenylalanine solution, and 2 ml distilled water and water bathed the mixture for 30 min at 30 • C. A total of 0.2 ml 6 mol/L hydrochloric acid solution was added to terminate the reaction.…”